Bug 216341 - busy loop in malloc can hang the machine
Summary: busy loop in malloc can hang the machine
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Fedora Legacy
Classification: Retired
Component: glibc
Version: rhl9
Hardware: All
OS: Linux
medium
high
Target Milestone: ---
Assignee: Fedora Legacy Bugs
QA Contact: Brian Brock
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2006-11-19 15:44 UTC by Julien Ducourthial
Modified: 2016-11-24 15:01 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2007-08-30 19:57:30 UTC
Embargoed:

Attachments (Terms of Use)
program to show the problem (2.15 KB, text/x-csrc)
2006-11-19 15:44 UTC, Julien Ducourthial 		no flags Details
patch to correct the problem (2.29 KB, patch)
2006-11-19 15:49 UTC, Julien Ducourthial 		no flags Details | Diff
View All

Description Julien Ducourthial 2006-11-19 15:44:29 UTC 
Description of problem:
when using real time thread (with SCHED_FIFO policy) and malloc, the machine can
get stuck in malloc when another thread is doing some fork.
After checking the source there is a busy loop in get_arena2 (in malloc/arena.c)
which can occurs in fork situations. 
This problem have been corrected in RHEL3.

Version-Release number of selected component (if applicable):
2.3.2-27.9.7

How reproducible:
systematic

Steps to Reproduce:
1. log in as root
2. run the attached program malloc_bug
3. 
  
Actual results:
the program aborts because it detects a hang situation

Expected results:
the program shall run flawlessly.

Additional info:
Comment 1 Julien Ducourthial 2006-11-19 15:44:29 UTC 
Created attachment 141584 [details]
program to show the problem
Comment 2 Julien Ducourthial 2006-11-19 15:49:21 UTC 
Created attachment 141585 [details]
patch to correct the problem

this patch is a backport of the patch that was done by U.Drepper on
glibc-2.3.2-95.31 to correct the problem on RHEL3.
Comment 3 Jesse Keating 2007-08-30 19:57:30 UTC 
Fedora Legacy project has ended.  These will not be fixed by Fedora Legacy.
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